diff --git a/admin-web/src/views/Conversation.vue b/admin-web/src/views/Conversation.vue
index 1b5ed4e..5db3984 100644
--- a/admin-web/src/views/Conversation.vue
+++ b/admin-web/src/views/Conversation.vue
@@ -220,7 +220,9 @@ function formatAccountName(id: number | undefined) {
 const filteredBindAccounts = computed(() => {
   const channelType = currentBindConversation.value?.channelType
   if (!channelType) return accounts.value
-  return accounts.value.filter((a: any) => a.channelType === channelType)
+  return accounts.value.filter((a: any) =>
+    a.channelType?.toLowerCase() === channelType?.toLowerCase()
+  )
 })
 
 function formatConversationType(type: number | undefined) {
@@ -337,7 +339,10 @@ function openBindAccount(row: any) {
 }
 
 async function handleBindAccount() {
-  if (!bindAccountForm.accountId || !currentBindConversation.value) return
+  if (!bindAccountForm.accountId || !currentBindConversation.value) {
+    ElMessage.warning('请选择账号')
+    return
+  }
   try {
     await bindConversationAccount(currentBindConversation.value.id, bindAccountForm)
     ElMessage.success('绑定成功')
@@ -348,8 +353,8 @@ async function handleBindAccount() {
   }
 }
 
-const currentConversationId = ref<number | undefined>()
 
+const currentConversationId = ref<number | undefined>()
 const bindTagsVisible = ref(false)
 const bindTagsForm = reactive({
   tagIds: [] as number[],
diff --git a/backend/mci-server/src/main/java/com/sino/mci/send/service/SendService.java b/backend/mci-server/src/main/java/com/sino/mci/send/service/SendService.java
index 30577d8..65a227f 100644
--- a/backend/mci-server/src/main/java/com/sino/mci/send/service/SendService.java
+++ b/backend/mci-server/src/main/java/com/sino/mci/send/service/SendService.java
@@ -364,13 +364,9 @@ public class SendService {
             throw new BusinessException("租户未配置可用发送账号: channel=" + channelType.name().toLowerCase());
         }
         ChannelAccount account = accountMapper.selectById(accountId);
-        if (account == null || !tenantCode.equals(account.getTenantCode())
-                || account.getStatus() == null || account.getStatus() != STATUS_ENABLED) {
+        if (!AccountSelector.isHealthy(account, tenantCode, channelType)) {
             throw new BusinessException("租户没有可用的发送账号: channel=" + channelType.name().toLowerCase());
         }
-        if (!Objects.equals(channelType.name().toLowerCase(), account.getChannelType())) {
-            throw new BusinessException("单聊发送账号渠道类型与目标身份不一致");
-        }
         SendTarget target = new SendTarget();
         target.setConversationId(null);
         target.setPersonId(personId);
diff --git a/backend/mci-server/src/test/java/com/sino/mci/channel/service/ConversationServiceTest.java b/backend/mci-server/src/test/java/com/sino/mci/channel/service/ConversationServiceTest.java
index ed4a385..01a62bf 100644
--- a/backend/mci-server/src/test/java/com/sino/mci/channel/service/ConversationServiceTest.java
+++ b/backend/mci-server/src/test/java/com/sino/mci/channel/service/ConversationServiceTest.java
@@ -12,6 +12,7 @@ import com.sino.mci.crm.repository.TagMapper;
 import com.sino.mci.exception.BusinessException;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.ArgumentCaptor;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.junit.jupiter.MockitoExtension;
@@ -81,7 +82,56 @@ class ConversationServiceTest {
         BindConversationAccountRequest request = createBindRequest(10L);
         conversationService.bindAccount("tenant", 1L, request);
 
-        verify(bindingMapper).insert(any(ChannelAccountConversation.class));
+        ArgumentCaptor<ChannelAccountConversation> captor = ArgumentCaptor.forClass(ChannelAccountConversation.class);
+        verify(bindingMapper).insert(captor.capture());
+        ChannelAccountConversation binding = captor.getValue();
+        assertEquals(10L, binding.getAccountId());
+        assertEquals(1L, binding.getConversationId());
+        assertEquals(1, binding.getBindingType());
+        assertEquals(0, binding.getSortOrder());
+        assertEquals(1, binding.getStatus());
+    }
+
+    @Test
+    void bindAccount_defaultsSortOrderToZeroWhenNull() {
+        Conversation conversation = createConversation();
+        ChannelAccount account = createAccount(10L, "wecom");
+
+        when(conversationMapper.selectById(1L)).thenReturn(conversation);
+        when(accountMapper.selectById(10L)).thenReturn(account);
+
+        BindConversationAccountRequest request = createBindRequest(10L);
+        request.setSortOrder(null);
+        conversationService.bindAccount("tenant", 1L, request);
+
+        ArgumentCaptor<ChannelAccountConversation> captor = ArgumentCaptor.forClass(ChannelAccountConversation.class);
+        verify(bindingMapper).insert(captor.capture());
+        assertEquals(0, captor.getValue().getSortOrder());
+    }
+
+    @Test
+    void bindAccount_rejectsConversationFromDifferentTenant() {
+        Conversation conversation = createConversation();
+        conversation.setTenantCode("other-tenant");
+
+        when(conversationMapper.selectById(1L)).thenReturn(conversation);
+
+        BindConversationAccountRequest request = createBindRequest(10L);
+
+        BusinessException ex = assertThrows(BusinessException.class,
+                () -> conversationService.bindAccount("tenant", 1L, request));
+        assertEquals("会话不存在", ex.getMessage());
+    }
+
+    @Test
+    void bindAccount_rejectsConversationNotFound() {
+        when(conversationMapper.selectById(1L)).thenReturn(null);
+
+        BindConversationAccountRequest request = createBindRequest(10L);
+
+        BusinessException ex = assertThrows(BusinessException.class,
+                () -> conversationService.bindAccount("tenant", 1L, request));
+        assertEquals("会话不存在", ex.getMessage());
     }
 
     private Conversation createConversation() {
diff --git a/backend/mci-server/src/test/java/com/sino/mci/send/service/SendServiceResolveTargetTest.java b/backend/mci-server/src/test/java/com/sino/mci/send/service/SendServiceResolveTargetTest.java
index 80e79d6..263459d 100644
--- a/backend/mci-server/src/test/java/com/sino/mci/send/service/SendServiceResolveTargetTest.java
+++ b/backend/mci-server/src/test/java/com/sino/mci/send/service/SendServiceResolveTargetTest.java
@@ -183,7 +183,7 @@ class SendServiceResolveTargetTest {
 
         BusinessException ex = assertThrows(BusinessException.class,
                 () -> sendService.resolveTestTargets("tenant", createPersonRequest()));
-        assertEquals("单聊发送账号渠道类型与目标身份不一致", ex.getMessage());
+        assertEquals("租户没有可用的发送账号: channel=wecom", ex.getMessage());
     }
 
     private SendTestRequest createConversationRequest(String strategy) {